Friday, March 27, 2015

Cape Cutter 19 Launch in Cape Town

Nick Kulenkampff, of Cape Town, bought plans from us in November 2013 for the Cape Cutter 19, to be built in lapstrake plywood. I only received one question from him and that was on choice of plywood for the build. A few days ago I received another email from him, with launch photos attached. He launched his boat, named "Mimi", at Royal Cape Yacht Club, in February.

In his email, Nick said "thank you for a beautiful design and also for a set of plans that were spot on. I thoroughly enjoyed the entire process." From the photos it appears that he made a pretty good job of the build, which was also quicker than most at about 15 months.

This boat is available in GRP from Cape Cutter Yachts in UK. It is the smaller sister to our popular Cape Henry 21 design.

Here are some of Nick's build photos, with explanations
Making bulkheads. These are cut from full-size Mylar patterns, included in the plans.
Transom, laminated from multiple layers of plywood.
Bulkheads and transom set up on building stocks.
Bottom skin going on. Plenty of clamps needed.
Bilge panel gong on. Keel deadwood and wood bilge keels fitted. This bilge keel is to protect the hull when aground, serving purely as a support to keep the hull skin clear of pebbles.
Forward bottom panel. Fitting this panel is the most difficult part of the build, due to the amount of twist in the panel. The twist is what forms the fine bow for good performance.
Hull epoxy-coated, primed and ready for paint.
Building the cockpit. Nick's work is very neat.
Interior, looking forward, built  before fitting the deck.
Interior, looking aft. Painting in progress.
Deck stringers glued into pre-cut slots
Painted and brightwork being done. Almost ready to get wet.
This view shows why these little boats are so quick. That fine bow works vvery well.
Launch day. The yellow boat below the bow is "Black Cat", the Didi 38 that I built.
Afloat and waiting for her rig to be set up.
Thank you, Nick, for the set of photos. She looks good and I am sure you will have many good times sailing her.

To see more of this and out other designs, visit

Tuesday, March 24, 2015

Didi 29 Retro Progress

Bruce Mierke is building a Didi 29 Retro in Murphy, North Carolina. Bruce is a professional boatbuilder, building her for himself and progressing nicely. He has now completed the hull and it will be turned over in a few weeks.

This design is based on the Didi 26, modified to create a more classic image. Carrying a choice of rigs, the squaretop Marconi rig below and two gaff rigs further down the page. It is a radius chine plywood design, round bilge from plywood and can be built from plans or a CNC kit. Although Bruce is a professional builder, I developed this construction method primarily for amateurs and they have built many boats to this range of designs.
Marconi rig of Didi 29 Retro
Here are the latest photos from Bruce, showing the beautiful standard of finish that he has achieved.
Beautiful hull finish.
Two gaff rigs, racing at left and cruising at right.

For more info on this and our other designs, visit

Thursday, March 19, 2015

Dix 470 Catamaran Kit Build in UK

Kevin Bream is the owner of Exocetus Catamaran Kits in UK, the company that he formed to develop kits for our plywood catamaran designs and to market them to builders, both professional and amateur. To be sure that he does a proper job of this, he is building the Dix 470 himself, to test the fit of all parts and to develop systems to ease the whole construction process.

The number of plywood components in a boat like this is massive. Just the thought of figuring the size and shape for each one, then cutting it out before fitting it in place on the boat, can make the project being contemplated seem very intimidating. Anything that can be done to reduce the number of hours in the build and the flow of elbow grease from builder into the boat is worthy of consideration. It reduces building time for any kind of builder. For a boatyard it increases profits and for the amateur it gets him afloat and sailing sooner.

Kevin Bream has one hull completed and is now working on the second. Lessons that he learned while building the first hull have been put into making a better product. Aside from that, anyone who buys a kit from Exocetus will benefit from a product that has been built by the supplier himself. Who could provide better backup support to the builders than he who has done the development, the cutting and the building before them?

Here are recent photos of the project.
The workshop of Exocetus Catamaran Kits, first hull on the right.
Completed Dix 470 starboard hull, waiting for its mate.
Self-jigging building stocks, bolted to the concrete slab.
Interlocking bulkheads & backbone assembled, stringers in progress.
Daggerboard casing. This boat can have cruising keels or daggerboards.
Skeleton of port hull, ready for skin. The jigsaw joints are visible at panel edges.
Skeleton with side skin being dry-fitted to test for proper fit.
Stern detail of starboard hull, showing swim platform.
Exocetus Catamaran Kits can also supply similar kits for the bigger sister, the DH550.

To see more about these designs, as well as others of all types and materials, please visit

Wednesday, March 18, 2015

Don't Underload Your Diesel Engine

I have been around boats with diesel engines for more than 40 years. In that time I have heard many times that we should not run a diesel engine under light loads for long periods because "it can glaze the cylinders". Another statement has been "diesel engines like to be loaded". Maybe you have also been told or read this but do you really understand what is going on with your diesel, why it is so important to run it with healthy loads and why you should not over-power your boat?
turbine wheel
A turbo charger turbine wheel fouled with soot and fuel, the result of chronic underloading. This gunge also fouls your upper cylinders, exhaust valves and exhaust system. From there it is washed out with the cooling water into the water on which you enjoy your boating. Photo courtesy of Steve D'Antonio.

I am a proponent of reasonable size motors in sailboats but often deal with owners who want to put much bigger motors in their boats than I recommend. My 36ft boat had 20hp, my 34 had 12hp and my 38 footer had 18hp. That 12hp could push my boat against a 40 knot wind on flat water. Sure, it was slow progress and the motor was working very hard but it could do it. In less extreme conditions the motor wasn't just ticking over to move her at reasonable speed. A 20hp motor would still be acceptable on that boat but anything bigger would be over-powering it.

Professional Boatbuilder magazine has an enlightening article on this subject on their website, written by their technical editor Steve D'Antonio. Steve also works with owners and builders through his own business, Steve D'Antonio Marine Consulting, Inc.
cross hatch
The grooves that retain oil in a cylinder wall, known as crosshatch, can be seen here. Frequent light load operation can wear away this pattern; known as cylinder glazing, it exacerbates blow-by and the issues that accompany it. Photo courtesy of Steve D'Antonio.
I don't want to repeat here what Steve writes about so clearly in his article, just to point out again that you do harm to your motor, to your bank account and to the environment by over-powering your boat, which inevitably results in you running your motor at speeds that will cause problems. Those problems won't only materialise "in the long run", they can start to appear when the motor has run for no more than a few thousand hours. You will be inviting self-inflicted pain and heartache on yourself and future owners of the boat.

Please read Steve's article. And for info on my designs, please visit

Monday, March 9, 2015

Jim's Didi Sport 15 Nears Completion

Followers of this blog have read about the DS15 being built by Jim Foot in Port Elizabeth, South Africa. His project is nearly done and is looking great. He is into the rigging stages and should launch in a few weeks.

Foredeck and mast deck panels fitted.
Foredeck almost complete. Spinnaker chute on right of centreline.
Jim's DS15 tries her dolly for size, showing her clean, modern hull.
DS15 shows her bottom and her performance potential.
Clean lines and powerful stern.
Mast and standing rigging, waiting for her sails.
Next instalment should be launching and sea trials in a few weeks. Until then, see more at

Thursday, March 5, 2015

Yachting Monthly Capsize Video

Yachting Monthly have a very interesting  video of a capsize test on their YouTube Channel. I only became aware of it yesterday when it was highlighted by Scuttlebutt Sailing News.

Many have read the accounts that I have written about our capsize experience on the Didi 38 "Black Cat" in the Cape To Rio Race 2014. It is not possible to visualise what it is like to be there in that situation, even if you sit inside your boat and try to imagine it turning around you but this video goes a long way to help visualise it. It is not fully realistic because the roof stays at the top as the boat rotates, so the world is rotating around the boat rather than the boat rotating within the world around it. To provide better visualisation the camera needs to stay upright while the boat goes upside-down.

Bear in mind that this test is in flat water and the boat is rotated quite slowly from upright to upside-down, then rights itself quickly. Normally a capsize will happen in seas that are large and confused, so it is a much more violent process than seen in the video, with the boat being thrown in confused directions while it capsizes. Despite that, it is worth watching, to see the way that crew, equipment, etc was moved around the cabin and to see just how much water came in even in that still water.

It is not an experience that I would recommend to anyone, yet it is an experience that I am glad to have had and to have survived.

It also validates the toughness of the methods of construction that I have used for these plywood designs, that "Black Cat" came through with minimal damage.

To see our range of designs to carry you across the dam or around the world, please visit